Vietnam's navy conducted live-fire artillery drills off its central coast Monday, following rising tensions with China over control in the South China Sea.

The maneuvers began near an unoccupied island about 40 kilometers off the coast of Quang Nam province.

Hanoi described the exercises as “routine training,” but Chinese state media strongly criticized the drills as “a military show of force to defy Beijing.”

The media also called the maneuvers a test of China's resolve after two recent incidents in which Chinese vessels interfered with oil exploration ships operating within an area Vietnam claims as its exclusive economic zone. China claims jurisdiction over the waters where the incidents happened and has warned Vietnam not to provoke matters further.

The growing tensions between China and Vietnam stem from competing territorial claims to two energy-rich archipelagos also claimed by the Philippines, Malaysia, Brunei and Taiwan. The Paracel Islands and the Spratlys also straddle strategic international shipping lanes.

In Washington, Senator Jim Webb , who heads the Senate Foreign Relations subcommittee on East Asia, said Monday the U.S. should make it clear that it opposes use of force by China in asserting territorial claims in the South China Sea. Webb said he plans to submit a Senate resolution condemning China's actions.

Vietnam charges that in the first incident late last month, Chinese naval craft deliberately cut a cable trailing from an exploration ship. China says the second incident was an accident in which a fishing boat became entangled in an exploration cable.

Vietnam called for international mediation of the dispute, but China has said it wants to settle the issue on a bilateral basis.

The territorial dispute with China is expected to be a major issue at the ASEAN Regional Forum in July.